What does it mean diff_opt = -1?

[mmi]

Hi,

According to your website (Namelist Variables — WRF Users Guide documentation), the default option for diff_opt is -1. However, there is no explanation about what that means. I have checked the registry files Registry.CONVERT and Registry.EM_COMMON, and I have seen that the default option of diff_opt is indeed -1. Could you please explain what this value does?

Thanks in advance.

Marta

 

[Ming Chen]

Marta,
diff_opt = -1 indicates that no horizontal diffusion is calculated.

 

[mmi]

Hi Ming,
Thank you very much for your response.